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// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___BIT_BIT_CAST_H
#define _LIBCPP___BIT_BIT_CAST_H
#include <__config>
#include <cstring>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER > 17
template<class _ToType, class _FromType, class = enable_if_t<
sizeof(_ToType) == sizeof(_FromType) &&
is_trivially_copyable_v<_ToType> &&
is_trivially_copyable_v<_FromType>
>>
_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI
constexpr _ToType bit_cast(_FromType const& __from) noexcept {
return __builtin_bit_cast(_ToType, __from);
}
#else _LIBCPP_STD_VER > 14
template<class _ToType, class _FromType, class = enable_if_t<
sizeof(_ToType) == sizeof(_FromType) &&
is_trivially_copyable<_ToType>::value &&
is_trivially_copyable<_FromType>::value
>>
_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI
constexpr _ToType bit_cast(_FromType const& __from) noexcept {
_ToType __to;
::memcpy(&__to, &__from, sizeof(__from));
return __to;
}
#endif // _LIBCPP_STD_VER > 17
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___BIT_BIT_CAST_H
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